Gas-engine.



No. 706,!67. Patented Aug. 5, I902.

T. DOHERTY.

GAS ENGINE.

(No Model.) 2 Sheets-Sheet l,

Patented Aug. 5, I902.

T. DOHERTY.

6 AS E N GIN E.

(Application filed Jan, 3, 1902.!

2 Sheets$h eet 2.

(No Model.)

rrnn- STATES PATENT OFFICE.

THOMAS DOIIERTY, OF SARNIA, CANADA.

GAS-ENGINE.

SPECIFICATION formingpart of Letters Patent No.-706,167, dated August 5, 1902.

Application filed January 3,1902. Serial No. 88,324. (No model.)

I it appertains to make and use the same.

My invention relates to explosive gas-engines of the multiple-piston type; and it consists, essentially, of the general arrangement and combination of the various parts, as will be hereinafter fully described, and particularly stated in the claims.

One of the principal objects of the invention is the production of a light and economical yet powerful engine in which vibration will be reduced to a minimum.

A further object is to so construct, arrange, and connect the various parts that a much greater length of stroke will be obtained than is usual in this type of engine. Further 2 5 objects of the invention will become apparent upon a detail description thereof.

In the drawings, Figure 1 is a perspective view of my improved gas-engine; Fig. 2, a similar View of the pistons and crank-shaft 0 and their connections; Fig. 3, a longitudinal horizontal section of the engine; and Fig. 4, a detail View of the outer end of the cylinder, showing the guide slots or ways in which operate the ends of the cross-head.

Referring to the several views, the letter a indicates the cylinder, which consists of a casting properly bored and provided at one end with a suitable crank-case b. J ournaled in the side walls of the crank-case in suitable boxes 0 is a crank-shaft 0, provided with reso as to bring it into proper alinement with the wrist-pin of the crank. Connected to crank c is one end of a pitman (K the other end of said pitman being attached to a cross head (i which has its respective ends connected to a cross-bar (l by connecting-rods d The cross-bar d is secured to a piston-head e, and the said rods are offset, as shown at cl",

to properly aline them with the wrist-pin of crank 0 The outer end of the cylinder is provided with oppositely-disposed guide-slots a, as shown in Fig. 4-, in which the outer ends of the cross-head d are adapted to reciprocate and be guided in a true line, and the crank-case is provided on two of its inner walls with guide slots Z), one of which is shown in Fig. 3, in which reciprocates the outer ends of the cross-bar (Z The cylinder is incased by a suitable water-jacketj'.

The letter 9 indicates a suitable boxing or casing, containing the usual oil or gas inlet valve 9, admitting oil or gas into the chamber formed between the two pistons, 91 the exhaust-valve, and h the vaporizer, which may be of any approved construction.

The letter i indicates an ordinary sparkerplug,'7c a suitable timing-pinion for the igniter, and m the starting-clutch, which may be of any suitable construction.

The crank-shaft is provided with a balance-wheel n, which is much lighter than those ordinarily employed on this class of engines, owing to the force being so exactly divided that the pistons and cranks partially aid by their own momentum to carry the pistons over the compression in starting.

In operation the charge is exploded between the pistons, and the explosive force of the charge drives the pistons in opposite directions, causing them to revolve the cranks, and thereby the crank-shaft. The explosion occurs at every second inward movement of the pistons, and the exhaust of the gases takes place in the usual way.

The compression may be varied by the adjustment of the jam-nuts n and n on the outer piston, so as to give more or less compression to adapt the engine to either gasolene or manufactured gas as a fuel or to a lighter or poorer gas of any kind, as may be desired.

Having thus fully described my invention, what I claim, and desire to secure by Letters Patent, is-

I. In a gas-engine, the combination with a cylinder provided at one end with a crankcase, of two pistons adapted to operate within the cylinder, a double crank-shaft, one of said cranks being connected to one of the pistons by a single offset pitman, and the other crank connected to the other piston by a straight pitman and two ofiset connectingrods, and means for supplying and exploding an explosive charge between the pistons.

2. In a gas-engine, the combination with a cylinder provided at one end with a crankcase, of a two-throw crank-shaft jonrnaled in the walls of the crank-case, and two pistons, one of which is connected to one of the cranks by an ofiset pitman, and the other piston provided with a cross-bar which is connected to a. cross-head by ofiset connecting-rods, said cross-head being connected to the crank by a straight pitman, substantially as specified.

3. In a gas-engine, the combination with a cylinder provided at one end with a crankcase, the other end of said cylinder being provided with oppositely-disposed guide-slots, and the inner wall of the crank-case provided with guide-grooves, of a two-throw crank 20 shaft j on rnaled in the side walls of said crankcase, two pistons adapted to operate in the cylinder, one of said pistons being provided with a cross-bar adapted to reciprocate in the guide-grooves of the crank-case, the said cross-bar connected by offset rods to a cross head adapted to reciprocate in the guideslots in the end of the cylinder, said cross head being connected to one of the cranks, and the other piston connected to the other crank by an oifset pitman, whereby the force of the explosion between the pistons, moving them in opposite directions, is transmitted to the shaft.

In testimony whereof I affix my signature in the presence of two witnesses.

THOMAS DOHERTY. 

